1. Cut out carbs at dinner.

The quickest way to shed a few pounds immediately is to keep your dinner plate clear of carbohydrates, according to Shapiro.

"That's one of the first tips I always tell my clients," Shapiro said. "I don't believe in going carb-free, but an easy way to drop pounds is to cut carbs at dinner."

Carbs are the body's first source of energy, but people don't really need energy to sleep.

"If you eat them at lunch, you're generally going to burn through them before you go to bed," the nutritionist said. "But if you eat them at dinner, you are less likely to burn through them before you go to bed."

Shapiro told INSIDER that she doesn't just mean the obvious culprit: bread. Instead, she said people need to cut even healthy carbs, including quinoa, brown rice and sweet potato, to see results.

"Usually I say just focus on protein and veggies for dinner," Shapiro said.

2. Drink more water.

Getty Images/Matt Cardy

A lot of times, after a holiday weekend, we feel totally bloated because we've consumed way too much beer, salty snacks and barbecue.

To get rid of that bloat, Shapiro recommends turning to the oldest trick in the book — drinking more water.

"Drinking water helps to keep you full, but also helps to flush out any of the extra sodium or bloat that we're holding onto," the nutritionist said.

Immediately post-holiday, she suggests people drink anywhere from 10 to 12 cups a day for a few days.